Page 138 - Webster's Speller

a. When the noun ends in e, if s will coalesce with the preceding consonant, it does not form an additional syllable.
bride, brides; blade, blades; simile, smiles; knave, knaves; date, dates; note, notes; bone, bones; cake, cakes; flame, flames.
b. If s will not coalesce with the preceeding consonant, it unites with the e and forms an additional syllable.
grace, gra-ces; spice, spi-ces; maze, ma-zes; fleece, fleec-es; pledġe, pledġ-es; staġe, staġ-es.
14. When nouns end in ch, sh, ss, and x, the plural is formed by the addition of es.
church, churches; peach, peaches; bush, bushes; glass, glasses; dress, dresses; fox, foxes.
15. Nouns end in y after a consonant, form the plural by the changing of y into i, and is addition of es; the termination ies being pronounced īze, in monosyllables, and ĭz in most other words.
fly, flies; crȳ, cries; skï, skies, cit-y, cit-ies, du-ty, du-ties; glo- ry, glo-ries; ru-by, ru-bies, la-dy, la-dies; fu-ry, fu-ries; ber- ry, ber-ries; mer-cy, mer-cies; va-can-cy, va-can-cies.
16. Nouns ending in ay, ey, oy, ow, ew, take s only to form the plural.
day, days; way, ways; bay, bays; de-lay, de-lays; val-ley, val- lēys; mon-ey, mon-eys; at-tor-ney, at-tor-neys; sur-vey, sur- veys; boy, boys; bow, bows; clew clews.
17. Nouns ending in a vowel take s or es. sea, seas; hoe, hoes; woe, woes; pie, pies.
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